text:
Can a plane land on an aircraft carrier without support from its crew?
Imagine a scenario where a carrier was dead in the water. No-one inside. Could a plane land on the carrier? What would such a procedure look like potentially?

I guess it depends on where you draw the line between landing and crashing.

Carrier landings are crashes, just controlled crashes.

I would be concerned about an active Phalanx Close-In Weapons System (CIWS)

The Nimitz Class aircraft carriers are the largest warships ever built. With over 6,000 personnel (crew and aircrew), the carrier has a displacement of 102,000t, and a flight deck length of 332.9m.

From: Nimitz Class Aircraft Carrier - Naval Technology
https://www.naval-technology.com/projects/nimitz/
332.9m * 39 in/m * 1 ft/12in = 1081.9 ft.  I think many small (2-4 seat) aircraft could land & stop in that distance. I'm pretty sure I could in my Cessna 177B, fixed gear, with micro-vortex generators for slower landings. Even without any headwind to help slow down.
From the 177B Pilot Operating Handbook:

LANDING PERFORMANCE:
  Ground Roll    ---------------------------------------------------- 600 FT

And that was before the micro VGs, so it should be even shorter now.

Pretty sure a Cessna was landed on a carrier during the fall of Saigon... EDIT: https://en.wikipedia.org/wiki/Operation_Frequent_Wind a Cessna O-1 piloted by Major Buang

Scrolling down, I was thinking that the O-1 looked a lot like a C-170:   "The U.S. Army issued the specification for a two-seat liaison and observation monoplane, and the Cessna Aircraft Company submitted the Cessna Model 305A, a development of the Cessna 170. The Cessna 305A was a single-engined, lightweight, strut-braced, high-wing monoplane with a tailwheel landing gear. The greatest difference from the Cessna 170 was that the 305A had only two seats, in tandem configuration (the largest tandem-seat aircraft Cessna ever produced), with angled side windows to improve ground observation. "

The Cessna was landed with cooperation of the carrier. In fact, the deck crew dumped viable aircraft overboard to make room for the Cessna to land.

@dotancohen the OP's question doesn't state anything about the deck being not clear, and in this particular instance, the carrier had its flight deck obstructed due to the extraordinary circumstances it was operating in.

Maybe I should not have added that second sentence. The OP does mention that the carrier should not be actively cooperating. Wikipedia has a photo of yellow shirt deck crew directing the landing.

@dotancohen that yellow shirt is marshalling the taxi along the deck, which is arguably more complicated as ground visibility takes a lower priority in aircraft design and the deck was quite crowded on this occasion. If you want to argue that it would have been impossible or unduly difficult to land that same aircraft without Paddles, go ahead, but I'm unconvinced, that kind of assistance is mostly for jets that: a) need to catch an arresting wire, b) handle like a cow at low speeds and c) come in with nose high.

@dotancohen The helicopters shoved overboard to make room belonged to the Army.  The sailors probably viewed them as more clutter than anything else; and were already shoving helicopters overboard as needed because the number of South Vietnamese choppers flown oneway to the ships greatly exceeded the available deck/hanger space.

The Cessna landing also involved getting up more steam then they had been using to land the planes they expected (or so I heard from a guy who was in the engine room at the time). On the other hand, the Midway was a big ship by WW2 standards but not really in the same class as a super-carrier. My source also talks about being asked to make black smoke (usually a mortal sin) so that planes without navigation support could find them.

@dmckee after it's 1970 refit the Midway had the same angled deck plan as more modern USN carriers, and had length/width (at flight deck) sizes within 10% of a Nimitz class.  It had a much lower displacement; but that isn't a factor in landing an airplane on the flight deck.

Most carrier-borne aircraft can't: they need (at a minimum) the arrestor wire system to be functional and set to the correct weight.
As jwenting said, smaller aircraft may be able to. A C-130 Hercules famously landed on a carrier (without arrestor hook), but that may have required wind over the deck (i.e. the carrier steaming against the wind at high speed).

"Against the wind" is a good point. The carrier might not be in the right orientation, which could greatly hinder the landing.

The initial tests were done with a 40-50 knot wind speed on the nose of the aircraft.  It's not immediately clear what the following tests were at, but even at max payload the C130 had plenty of spare deck space even without using an arrestor hook or catapult (and with lighter loads could take off from where it stopped on the landing).  the limiting factor that caused the Navy to go with a smaller aircraft was that the c130's wing had so little clearance with the island that it would be a disaster waiting to happen. https://theaviationist.com/2014/07/16/c-130-land-on-carrier/

As I recall from video of that C-130 landing, the plane had nose art that said, "Look Ma, no hook!"

@FredLarson You are correct.

All VTOL's (Vertial takeoff or landing) planes will be able to land on an abandoned carrier, as they need a vastly reduced runway; it would be a bit like landing a helicopter.
They will do so though at the cost of a huge amount of fuel and coolant; which may mean that they could struggle to do a return trip if they can't refuel.

As I understand it, fuel isn't the real issue here.  The Harrier was limited to ~20s of VTOL because it would run out of water, which was used as a coolant.  Beyond that the engines would overheat and stop working.  Not an issue in flight, as the wings produce lift, it isn't just the raw power of the engine.

@Baldrickk very true - updated.

The Harrier could, certainly. It was designed to land with zero runway, and in any conditions. The V-22 and F-35, less so. Both have fearsomely hot exhaust which will melt metal, so carriers are being outfitted with cooling on runways. One of those could land on a carrier, certainly. More than one would be a risk in case they landed with some forward speed and hit a deformed area of runway. But however many you landed, none would be taking off again until the carrier had had major repairs.

@Graham "none would be taking off again" - why? It seems reasonable that after such an emergency VTOL landing, one of these could taxi 50 feet to a "fresh" section of runway and take off vertically again.

@Graham let me highlight the "Vertial takeoff" part of the VTOL.  If the aircraft was refuelled then there's no reason for it to not take off (note here that I'm considering coolant a form of fuel in this statement).  It's also out of scope as the question is strictly "land".

I'm surprised this is the only answer to mention VTOL/STOVL aircraft, which was the first thing that came to my mind - but then being British I've grown up seeing TV footage of Harrier's landing on carriers.

This becomes increasingly obvious in consideration of the fact that the USN's COD role is transitioning to the V22 anyway.

Depends what's on the deck
Carriers often stuff the deck with aircraft, or have the deck disrupted for other reasons.  If the evacuation interrupted an evolution when the deck was cluttered or in repair, they may have just left it that way, and you could have a much smaller space to land in.
Also, the evacuating forces are not fools.  They will have made a fair effort to prepare the flight deck for whatever they expect to happen next.  If friendly rescue is all but certain, they may clear the landing deck. Otherwise they would intentionally block it by positioning forklifts, tugs or (loaded?) ammo carts specifically to prevent an adversary from doing what you intend. Would they have time? Surely - a carrier takes a long time to evacuate.
Check the weather
That said, you will have no trouble finding a variety of aircraft capable of even a desperation 1/8 deck landing that involves stopping by crashing into a forklift.
The weather will be a significant factor!  If there is a significant wind, it then matters whether the wind is aligned with the deck, or crosswind to it.
Further, if the wind is high enough, you would be able to do essentially vertical landings using low stall-speed aircraft.  Here, our go-to bird is the Antonov-2.

This thing is called the "Colt" but it's a beast. I chose that picture to show you how enormous it is.  4700 pounds of useful load (15 men and gear) and a stall speed of 30 mph, so in 26 knot wind it can essentially vertically land.  That means viable landing in a worst-case crosswind.  However for this same reason, you'll need to tie it down immediately on landing, or the wind could take it.  So your crews better train that!
The Antonov-2 and brother
Range is 525 miles on 800 litres of fuel, but you can "turn it into a flying gas can", trading useful load for extended range at about 2 pounds per mile.  Doing so actually  works in your favor, since this will mean a lighter landing weight and thus a slower landing.
It is also feasible to use a variety of ships as an ad-hoc carrier for the An-2 or many other STOL aircraft, as long as a short runway could be improvised.  The wind that makes landing favorable would also aid takeoffs.  A container ship might be a good choice.  Containers have varying height, so certain ones could be selected to yield an even top surface, with some welded-up bridge panels for the gaps.
Suffice it to say, you could land quite a significant force on this abandoned carrier with a squadron of An-2‘s.
You may also consider the An-3, a factory upgrade to a turboprop engine that may buy you some cargo capacity and/or range: one big advantage is that you can refuel an An-3 from the carrier's stores of jet fuel; carriers do not stock aviation gasoline.  However, An-2's are plentiful and in service.  An-3's are rare enough that if you acquire one of them (let alone sixteen), someone's bound to notice.
The An-2/3 isn't actually Russian, it's Ukranian.  Further, it's also manufactured in Poland under license, and while the FAA obstructs registration of Soviet bloc aircraft in the US, we have a trade treaty with Poland whose effect is Polish built An-2‘s are allowed.
Open the deck
Once you have a force on board and are able to clear the deck, this would open to larger STOL cargo aircraft such as a DHC-5 Buffalo, which has meaningfully greater cargo capacity.  However, these aircraft made in low production, so it's the same "people are going to notice" problem as you acquire aircraft and parts.
Only after the carrier is made operational and able to self-propel into the wind, could you consider larger STOL craft like the C-130. Again, if the crews intended it, on their way out, they could assure no one but a heavy drydock could get it operational.  In particular, nuclear reactors are not to be trifled with.

"If there is a significant wind" (there almost always is at sea) there will be a swell, which means the deck is rolling and pitching as you land on it.

@TimLymington all the better.  As you get very close to the deck, the wind slows because of surface effects, and you could potentially stall the aircraft and drop hard.  With a pitching deck, you let the deck come up and meet you, shortening that "stall" period.

Planes specially modified for short landing would be able to land in almost any conditions - some even across the flight deck instead of along it.
However, considering an aircraft carrier dead in the water would be a suspicious occurrence, I suppose the "plane" used would be an V-22 Osprey, with the option of vertical landing.
The operation would use naval fighters in top cover, more naval fighters in bombing configuration, electronic warfare birds (for jamming anything), probably a submarine for underwater cover, and probably many more things.
The Marines would fly in helicopters or Ospreys at sea level and rappel down (probably) above the carrier. Landing planes on the carrier might not take place until the carrier is considered "secure" - six Ospreys might be used to rappel down about 200 marines (or SEALS).
Also, SEALS might choose to swim to the carrier and enter it either via climbing to flight deck or other accessible entry points, or even breach (break) into it.
Here is an Osprey's vertical landing:

Depends on the aircraft, obviously.
Something that needs less runway to stop than the length of the landing area of the flight deck should have no problems.
Of course that's assuming the deck is clear and the aircraft small enough to not hit the island or other obstacles.
Something like a Piper Cub or Beaver could probably do it. An F/A-18 likely could not.


text:
Does the "bat wing" aircraft paint design have a proper name?
I would like to do a web search for different planes that have utilised the "bat wing" paint application noticeable on the wings below?  What keywords should I search for?

Although aeroalias is correct that this is often associated with Gee Bees, I think a more 'generic' term is a scalloped paint scheme, e.g.:

American Champion paint options
C130 paint schemes
Model biplanes

Scalloped is the term I was looking for but I am still unable to find many aircraft images (other than Gee Bees).  In case is due to my unfamiliarity with aircraft terminology can I ask what search terms you used to return those results?

@darmi I think I simply searched for "scallop paint aircraft" or something similar, I can't remember exactly

This particular paint scheme was used in a number of Gee Bee aircraft (in different colors) and is popularly called the 'Gee Bee paint scheme'.

GeeBee R2 Super Sportster By Netweave - Own work, CC BY-SA 3.0, Link
According to the book Gee Bee:

The Gee Bee's paint scheme was inspired by the Coca-Cola paint signs of the 1930s.

This page, where an image similar (same?) as yours is available also calls it the Gee Bee scheme:

Gee Bee paint schemes have been popular on Fly Babies, but have you ever wondered what one would look like with a small radial engine?

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


text:
Are the Gulfstream III's ailerons controlled by hydraulically boosted cables?
Are the ailerons for a Gulfstream III controlled cables with hydraulic boost? Also, is it possible that an aircraft mechanic could easily access the control to tamper with it?

I assume this is for your novel research. Note I think taking out the hydraulics would disable the tail & rudder (both not visible from the cockpit) so not fixable in your story. And weakening the mechanical cable to the ailerons might only disable the mechanical backup, so wouldn't be a credible sabotage.

@Andy, if just the ailerons cable (not the hydrologics) was tampered with that wouldn't affect the tail or rudder would it?

@Robert some mechanical details here might help. Maybe there's a crucial linkage he could snip somewhere (I really hope this is just for a work of fiction!)

At some point you might want to just hand-wave the details.  You're writing a novel, not a handbook on how to commit sabotage.  The few G-III mechanics that notice the inaccuracy will no doubt appreciate that you're not providing an instruction manual for bad guys.

@Andy I'd like to think anyone in a position to commit such a crime would already have the knowledge without Aviation.SE.

@Andy - Yes! - It's a science fiction novel. I want to make that very clear! See my blog https://novelwrites.com/my-books/ I think I am just going to go with a snipped cable and my alien controlling the failed aileron to save everybody. Dan is right - I really don't need in-depth detail - I just don't want to make something up that would look really silly for anyone with some knowledge of how a plane works...Thanks for the feedback!

Just a tip if you're new to Stack Exchange.  We do things differently around here compared to say Quora or Reddit.  We only deal in concrete questions which can be answered with concrete, factual answers. "Questions" discussing proposals, speculating, seeking opinions etc are off topic.  If you phrase your questions carefully, you can get the answers you need but best to avoid aliens and telekinesis, as you have done here.

I hope you haven't put yourself on an NSA watchlist :0

@Simon - I think I have chosen a poor way to conduct research for my science fiction novel - I didn't know it was going to get so complicated. I just wanted to write a plausible scene that makes my character a hero...sigh...thanks to everyone who responded.

@TomMcW I don't understand your comment - I don't really know what that would mean. I'm writing a science fiction action adventure book. Why would I be on a watch list for doing internet research when I am a writer?

@ngolden I'm just being facetious. Ever since Snowden spoke up I figure every time you you type words like "sabotage" and "airplane" in the same sentence it gets flagged for an analyst. Rarely are my comments to be taken seriously. Especially if there's an emoticon :)

@TomMcW Someone else in a previous comment alluded to that too so I was starting to wonder why...thanks for clarifying that you were teasing! I haven't seen Snowden but I just googled it and got your gist. Hopefully this book will be a bestseller and turned into a Hollywood screenplay and you'll get to see it at the movies :) I do plan on crediting the folks on S.E. in the acknowledgments. I am working hard to make the story enjoyable by at least showing the science is plausible. The fusion drive with an anti-proton energy source for interstellar space travel was a lot harder to research!

@ngolden I'm not sure that a cut aileron cable (even on a Gulfstream) is a scenario that requires outside help to safely land the aircraft. A pilot may be able to keep wings level with rudder.

Scary question are popping up lately, a few days ago was the guy who wanted to know it all about fire and fire detectors... :-/

Yes, the flight control surfaces on the Gulf Stream III are moved by cables with hydraulic assistance.
From a study guide for the type.

The flight controls on the G III are cable driven with hydraulic boost..  They are powered by both the "Combined" and "Flight" hydraulic systems.  Each of the systems provides 1500 psi to the flight control servo actuators.  When the landing gear or flaps are extended, the combined system pressure increases to 3,000 psi.  If one system fails, the remaining system pressure increases to 3000 psi.  Failure of one hydraulic system therefore, does not result in a loss of control effectiveness.

As to whether a mechanic could interfere with the controls, of course.  But for what purpose?  I am not sure that I understand what you mean by "tamper" but I assume that you mean sabotage. If so, then there are multiple ways to do this but I see no point in speculating as to what someone might do or why.

Re: for what purpose. According to OPs other question, they are writing a novel and want credible sabotage ideas. http://aviation.stackexchange.com/questions/31686/plausible-scenario-for-aircraft-sabotage-for-a-science-fiction-novel

@Robert Thanks.  I'll stay clear of the motivations :)

@Caterpillaraoz I really wish I never asked this question because people keep finding it concerning. Hopefully my science fiction novel that I am almost finished with will be picked up by a traditional publisher and you will be able to read how there was a problem with an airplane's aileron but one of my main characters (an alien from Kepler 186f) saves the day...please read my previous comments - thanks!

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
Why 360 degrees is in the top instead of 90 degrees in aviation?
Normally on 2D map, if there is point say A(0,0) in the center and there is point B in the 2nd quadrant . The angle is always in 90<=x<=180. But in aviation, it is 270<=x<=360 . Why ?
Treat this as a basic question.

I have no idea what you are trying to ask here.

Because of compass headings? I've never heard of a map liked you describe. Mathematical planes have angle systems that are 90 degrees rotated and counterclockwise from compass headings.

Normal maps have 0 or 360 degrees at the top, I've never seen a map with 90 degrees at the top.

Can you add an example of a "normal" map that has 90 degrees at the top? That might help to make your question clearer.

In the (really) old days, some maps had east at the top. "European cartographers oriented their maps towards the Holy Land since Jerusalem was the place of Christ’s death and resurrection.  In fact, the world “orient” comes from the Latin word “oriens”, meaning East." (snippet from https://www.geolounge.com/map-orientation/)

@J.Hougaard: The etymology of orient is associated with "rising", like rising Sun. More or less the same India-European proto-origin than "aurora". Occident itself comes from "falling down".

@KorvinStarmast Polar coordinate systems do not typically have 0° oriented in the "North" direction. The difference is between Cartesian coordinate system, and an Earth-Centered, Earth-Fixed (ECEF) or Geodetic system, which is used for navigation and mapping purposes.

@RonBeyer OK, fair enough, a more precise point.

Conventionally, geographical maps are shown with the North up and North is also by convention 0 degrees (or 360), which is equal to the compass heading of North. The angle increases clockwise, with 90 degrees being East. This is not specific to aviation; in fact during flight the preferred presentation is to have the map oriented such that the direction of flight is upward.
The mathematical plane you seem to describe on the left has the primary axis as the angular datum (also by convention, more info here and here). So the positive x-axis is 0 degrees. The angle increases counterclockwise, so the positive y-axis is 90 degrees.

Because that is how compass directions work. A magnetic compass points towards the [magnetic] North Pole, because of the way the Earth's magnetic field is oriented, which makes it very convenient to use north as a starting point when it comes to compass directions.

North is the starting point, and is equal to 0 (or 360) degrees. The number then increases clockwise.
This is in no way unique to aviation. Almost all types of navigation rely on this standard, including maritime and aviation.


text:
Is there a term for the general design used in most modern fighters?
Is there a term that encompasses the overall design of modern fighters (e.g. F-15, F/A-18, F-14, Su-27, Su-30,33,35,37, Mig-29, J-11, etc.), with dual vertical stabilizers, leading edge extensions, dogtooth extensions, very similar nose and canopy shape/profile, air intakes, dual engines, and so on?
I know they each fit into one or more of the air superiority, strike fighter or interceptor categories, but I'm looking for a term (if it exists) which describes and/or encompasses this particular design style. Or is "modern air superiority / tactical / strike fighter" as close as I'm likely to find?

Maybe by Fighter Generation?

@RonBeyer, but this is not any particular generation. F-16, Panavia Tornado, Mirage 2000 belong in the same generation as the above and don't share the design features.

"Modern" fighters? You are listing all 30-40 year old designs (Sukhoi's incremental improvements to the Su-27 names Su-30, 33, 34 and 35 don't really count as new design, nor does the J-11 that is also derived from Su-27).

I am pretty sure there isn't, because there isn't really any general design worth speaking of. The elements are either obviously preferred for the intended performance, or vary.

@JanHudec "Modern" is a subjective term. If you want to be particular, then I am talking about fourth generation fighters, I suppose. I'm not sure, precisely; that's why I asked the question. I was looking for an answer to the question more than for criticism of the question itself, fwiw.

That particular empennage design is called a “four poster” amongst the OEMs.  It’s popular because it provides both excellent longitudinal and directional stability with a minimum side profile.  As to leading edge extensions, I’ve heard of them referred to by aviation scholars as Leading Edge Extensions (LEXs) or Leading Edge Root Extensions (LERXs) they’re popular because they create a turbulent boundary layer over the inboard sections of the wing and fuselage which provides better high alpha controllability.  Canopies, such as those found on the Eurofighter Typhoon or the F-16 are sometimes called ‘blister’ or ‘bubble’ canopies because of their outraised profiles against the OML of the fuselage, providing the pilot unobstructed 360° visibility with a minimum of blind spots, so critical to air to air combat.  The serrated  or ‘dog tooth’ edges of panels are done to minimize the radar cross section around panels or skin joints.
I don’t know if there’s a particular name for such a fighter configuration, save that for that kind of a performance requirements and flight envelope, it just seems to work very well.  Similar to Bill Sweetman’s analysis in his article How the 747 Got Its Hump, given certain criteria and other demands on designing and building an airplane, this is just the best solution to the problem of designing a large twin engine fighter airplane.  It’s an open ended design so there’s no ‘right’ or ‘wrong’ answer here; it’s just certain solutions work better than others.
They don’t always follow the mold though.  Take Lockheed’s F-22 in comparison to Northrop’s F-23 design.  The YF-22 was a stout, little chunky, conventionally styled twin fighter with stealth characteristics, while the Northrop YF-23 had a trapezoidal planform with smooth, voluptuous curved surfaces and a large pelican tail with twin all moving ruddervators.  Both aircraft excelled at what they did; a high speed low observable air superiority fighter but seemed to come to very different conclusions.  While the F-23 lost the contract, its design philoophy did not go unnoticed.  The Sukhoi design bureau seemed to draw very similar layout conclusions in the development of their Su-50 stealth fighter.  The same is true of the F-35 vs the F-32 aircraft.  LMACO’s entry was very conventional and the Boeing jet was an ungainly, unconventional delta wing design with a pelican tail, laid out largely for simplicity and ease of manufacture (which didn’t work out!).

But there were grave differences between the jets- f35 did everything for cheaper and with no reconfiguration, while the f32 was subsonic, had to have some parts replaced in order to go hover/supersonic and was less of a complete package. So the design was not entirely the main reason for selecting the f35, rather the overall specifications.

Eh, cheaper?  LMACO lowballed their bid at 200 billion for the R&D plus unit costs in 2002.  This rapidly ran away to 391 billion by 2012.  So much for a bargain.  And technically neither the X-32 or X-35 were very much like their production designs that both companies submitted.

A bargain is always in comparison to something :)
Agreed on not being cheaper, but they did manage to squeeze more in one demonstrator, while the Boeing demonstrator had to be produced twice- one for the vertical takeoff and landing, and the other one- conventional, supersonic.
link- link.
I will look up further.

There were two examples of the X-35 as well.  On a CTOL capable and the other one STOVL capable.  The requirement of the JSF program was for two prototypes.  An no, being 200% over budget is NOT a bargain, it’s war profiteering!

I think that your comment is unfortunately irrelevant and subjuctive, no offense, about war profiteering. And please send references regarding the JSF program requirements and where its noted to have 2 prototypes.

No the Pentagon admitted as much about the JSF/F-35 program in 2012.  And both companies submitted two “experimental” prototypes for the JSF competition.

Rwferences to that?

https://thehill.com/policy/defense/217871-pentagon-lockheed-martin-agrees-to-settle-price-gouging-charges

Ok, I have learned. But 16 million is not war profiteering, although tou never know what goes on those levels. Sowhat do you say about the F35, a cool machine??

I can try and answer this question by referring to 2 angles of approach.
The first one is the demand, and this has to correspond with the basic laws of physics- meaning- today, we would want an aircraft that is capable of Mach 2, stealth, can achieve such and such turn radius by let's say, 30 AOA, carrying such and such armament, etc.
The second approach would be evolution. Just like in nature- they look that way because they evolved that way in order to achieve the demands noted above while trying their best by fighting the laws of physics.
a fish didn't become a bird in 1 day, same as one engineer decided one morning that he/she is gonna build the F22, just because he figured out the numbers.
It's a long process of trial and error.
For example- Jet engines need air, hence the big intake if front. They need yaw control- so they have a fin (1 or 2, depending on the characteristic of the aircraft in high AOA, like in the F15- that has 2, simply because if it had 1- it wouldn't have met any air during high AOA maneuvers and enter a spin very quickly).
The F16 has 2 lower fins in order to compensate for the loss of airflow on the rudder in these situations.
Phantoms were shot down a lot because the cockpit was like a tank- they couldn't see anything. F-16- almost 360 field of view. F-35- less outside view because first- they don't need to see a lot outside their screens, and second- to maintain a more streamline contour of the whole body for stealth.
Leading-edge extensions look that way because they produce more lift and maneuverability, and nothing more.. As the physicists found during tests.
As in every industry- all fashions go together with what works (same for evolution)m and progress slowly to a better result.
As for my opinion, I don't think that if you need a fast maneuverable aircraft- we will not see very different designs in the near future unless there is some breakthrough in flow mechanics or propulsion science.
It's only a methodology to look at this subject, and it's progressing all the time.
I never heard an including name for them though :)

" Leading-edge extensions look that way because they produce more lift and maneuverability, not more.." <-- something's missing there...

not more, meaning- nothing more than their intention.
Should I say- "and no more"?

That makes perfect sense now that you've explained it, unfortunately, I didn't read tat into it the first time. Maybe the extra . was confusing me - leading me to believe it should have been ,. and that there was supposed to be something between the comma and period.

Maybe "and nothing more.."?

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
How does the Learjet cabin pressurisation system work?
In one of the MAYDAY Air Crash Investigation episodes (about the Payne Stewart crash), the flight's emergency manual had the following information under the cabin pressurisation section:

NOTE: At 10,000 (± 500) Feet Cabin Altitude, control pressure to the
  outflow valve is trapped. This deactivates the Automatic Mode and
  stops cabin altitude from rising higher if the failure is in the
  automatic control system.

What does it actually mean? As the NTSB investigators mentioned, it sure does sound confusing.

If the pilots know the system, it isn't confusing at all.  It simply states that a solenoid valve closes causing the cabin pressurization system to go into manual mode and the pressurization controller cannot control the cabin pressure.
It is a feature of Learjets to prevent cabin pressurization issues in case the controller is faulty.
Since you reference the Payne Stewart accident you should also know there were other issues at play that did not cause the pressurization controller to fail.  It was one of the early Learjet 35's without an emergency pressurization system.


text:
What is your favorite aviation joke?
This is funny!
Please post jokes, pictures, cartoons, videos related to pilots, air/ground controllers, aircraft mechanics, flight/cabin/ground crew or anyone/anything related to aviation.
Rules

Any material should not be offensive, rude or insulting to any group.
If that material requires proper attribution, please verify that by posting it here, no copyright rules are being violated.
You can add your own personal story as a joke. However, this is not the Aviation Blog. We are quite active over there and will be very happy if you want to contribute. Please come visit the chat room Readback, and ping the owner of the room for permissions.
This post is not for rep generation, hence all posts should be wiki. Mods are watching, and one of them has a cattle prod (yes, the electric one).
The material you are posting should be strictly related to aviation.
Make sure that the post is readable, and properly formatted.
Brevity is a virtue.

Please remember:
Before flagging it as off-topic, or too broad, or low quality (really, doesn't that depend on you), please refer to this discussion behind the motive of this post. More information is present in the links in that question and the comment which follows.

I read the linked discussion and I'm voting to close. The argument for keeping the thread is "precedent" but the precedent in question is two old questions, both of which have been locked due to not being appropriate Stack Exchange content. So precedent actually says we close this.

The linked Meta discussion also has more votes saying to close than to keep this question. Maybe it should be migrated to Meta.Av?

@DannyBeckett It's not a discussion about how Aviation.SE should work so it's off-topic there, too. This sort of thing belongs on chat.

going by the favorites to upvotes ratio for this question, i will vote to reopen if it becomes available.  the rationale for keeping the "precedent" questions open should also be considered precedent.

http://www.youtube.com/watch?v=GDkTkpoyfL0

I have voted to close this because I don't think the mission of Aviation.SE should be being a joke site.

Maybe a joke.SE should be proposed?

@erich But the precedent questions weren't kept open. They're locked, which means that they can't be edited, answered or commented on but they're not deleted. The only reason they've not been deleted is that it was felt that they were OK questions when they were posted but times have moved on and standards have changed.

Pilots Vs Maintenance Engineers
After every flight, pilots fill out a form, called a “gripe sheet” which tells mechanics about problems with the aircraft. The mechanics correct the problems; document their repairs on the form, and then pilots review the gripe sheets before the next flight.
Never let it be said that ground crews lack a sense of humor. Here are some actual maintenance complaints submitted by pilots (marked with a P) and the solutions recorded (marked with an S) by maintenance engineers.
P: Left inside main tire almost needs replacement.
S: Almost replaced left inside main tire.
P: Test flight OK, except auto-land very rough.
S: Auto-land not installed on this aircraft.
P: Something loose in cockpit.
S: Something tightened in cockpit.
P: Dead bugs on windshield.
S: Live bugs on back-order.
P: Autopilot in altitude-hold mode produces a 200 feet per minute descent.
S: Cannot reproduce problem on ground.
P: Evidence of leak on right main landing gear.
S: Evidence removed.
P: #2 Propeller seeping prop fluid
S: #2 Propeller seepage normal – #1 #3 and #4 propellers lack normal seepage
P: DME volume unbelievably loud.
S: DME volume set to more believable level.
P: Friction locks cause throttle levers to stick.
S: That’s what they’re for
P: IFF inoperative.
S: IFF always inoperative in OFF mode.
P: Suspected crack in windshield.
S: Suspect you’re right.
P: Number 3 engine missing.
S: Engine found on right wing after brief search.
P: Aircraft handles funny.
S: Aircraft warned to straighten up, fly right, and be serious.
P: Target radar hums.
S: Reprogrammed target radar with lyrics
P: Mouse in cockpit.
S: Cat installed.
And the best one for last.
P: Noise coming from under instrument panel. Sounds like a midget pounding on something with a hammer.
S: Took hammer away from midget.
(Source)

Aviation related xkcd has to be here somewhere at least
https://xkcd.com/726/

Caption reads: "Don't click the wing."

appropriate to have an XKCD commic on a stack exchange website.

Please click here for the source of this image.

Tower: "TWA 2341, for noise abatement turn right 45 Degrees."
TWA 2341: "Center, we are at 35,000 feet. How much noise can we make up here?"
Tower: "Sir, have you ever heard the noise a 747 makes when it hits a 727?"

Saint Peter was standing at the Pearly Gates, and a pilot walks up and says "My name is Joe, I'm a pilot, I think you've got a place for me." Saint Peter starts flipping through his book. Flip, flip, flip... "Ah yes Joe, here you are. Take this golden staff, harp, and silk robe, and pass through to the right where you'll meet the choir you've been assigned."
A minute later, another man walks up. "Hello Saint Peter, My name is Bob. I'm a retired pastor. I think you've got a place for me." Saint Peter starts flipping through his book. Flip, flip, flip.... "Ah yes, Bob, here you are. Take this wooden staff, this ukulele, and this cotton robe, and pass through to the right where you'll meet the choir you've been assigned."
Bob says (a little miffed) "Well, alright I guess... but why did that pilot guy get all that fancy stuff?"
Saint Peter says "Well y'see Bob, we work on the cause-and-effect principle here. While you spent years preaching, most of your congregation was asleep. When Joe there was flying, everybody who flew with him was praying."

A beautiful young blonde woman boards a plane to New York with a ticket in economy.  Noticing an empty seat in first class, she moves up and sits down.
The flight attendant checks her ticket and tells the woman she needs to move back to economy.  The blonde replies, "I have never had this problem before. I'm going to sit here until we get to New York."
The captain, having been informed of the situation, goes back and tells the blonde that her assigned seat is in economy, and again, she replies the same.
Not wanting to cause a commotion, the captain returns to the cockpit to discuss the situation with the first officer.  The FO says his girlfriend is blonde, and that he'll take care of it.  He goes back and whispers something in the blonde's ear.  Immediately she gets up, thanks the FO profusely, and returns to economy.  The captain and flight attendant are stunned and ask the FO how he was able to so quickly diffuse the situation.
The FO replies, "I just told her that the first class section isn't going to New York."

Any material should not be offensive, rude or insulting to any group.

Recent research suggests that having fair hair can seriously damage a woman's career

Any reason the person has to be a woman, or a blonde, for the joke to be funny? I'd suggest revising.

@egid i welcome your edits.

I'd really appreciate it if you could make the attempt.

This picture always give me a good chuckle

As does this one

One day in the not too distant future, so the hoary old story goes, airliners will have only two crew members on the flight deck — a pilot and a dog. At the press conference on the occasion of the introduction of the first of those airliners, the journalists ask: "What is the job of the dog?"
Answer: "To bite the pilot if he touches the controls!"
Journalists: "Makes sense. But why keep the pilot in the cockpit?"
Answer: "Someone has to to feed the dog!"

(Source is Punditkitchen.com, but the page seems not to exist anymore)

The advantage of a twin engine plane over single engine?  The second engine gets you to the crash site faster.

The alternative way I've heard this is that "In a twin, when you lose one engine, you have the second to fly you to the crash site."

The image has been taken from ChickenWings Comics

A crew member just gets hired on as a new flight attendant.  On their very first flight the crew has a three day layover.  The captain shows the flight attendant around the city including some of the best restaurants and hotels.
When the crew is finally ready for their return trip they just can't find the new flight attendant anywhere.  The airplane takes off in half an hour and the new flight attendant is nowhere to be found.
The captain calls the hotel that the flight attendant is staying at, he gets put through to get room.  The flight attendant answers the phone, and the captain is freaking out he says "Why are you in your room!?  We are supposed to be in the air in 30 minuets!"
The flight attendant is in tears and replies "I am stuck in my room, there's no way out!"
The captain asks how this is possible, knowing it's such a nice hotel.
The flight attendant responds. "There's two doors, one is the bathroom, and the other says 'DO NOT DISTURB.'"

Controller: United 6, make a 360.
Pilot: Approach, this here is a 747 that costs \$12000 per hour to operate.  a 360 takes 10 minutes.
Controller: Great, give me a \$2,000 turn.

Pilot: Sydney Approach, United 5, 10,000. We happy to be visiting your little island, and we have the airport in sight 12 o'clock.
Approach: United 5, roger. Turn right, follow the coast, expect the visual for 35.

I don't get that second one...

@Johnny - I suspect the joke is missing the part where the aircraft is approaching from the north, and that Australia is not so little when you have to go all the way around it to make the visual 35.

@Johnny It's also sometimes heard as "Roger, cleared to circle the island twice, then expect the visual for runway 35."

SYD doesn't have a runway 35... or is that also part of the joke?

i never explain jokes

Guy I used to know but have since lost contact with had as his email signature "I'd rather smoke and fly than drink and drive".

Always thought that a rather good one.


text:
Why are these spec and serial numbers blank on a part's plate of a WWII US military plane?

These pictures are of a plate from WWII US military plane that crashed in the high mountains of central Japan.
People living there say that after the war officials recovered the crash sites and some parts were put on display in a museum nearby.  This plate is attached to a small metal box which is part of the museum collection.
It says "gear box type JH-1045" manufactured by "Jack & Heintz, Cleveland Ohio".
But SPEC. and SER. are blank.  I assume these are where the spec number and serial number should go?
It looks like somebody carefully cut those parts off the plate.  People there say that was not done after the recovery, so the plane was flying with this plate as it is.  Nobody remembers the type of aircraft nor where the rest of the wreckage went.  I do not know whether the numbers were scraped off before flight or were just originally not there.
Why are these spec and serial numbers blank on the parts plate of a WWII US military plane?
Regards,
Naoya

though it's hard to tell exactly from the pictures, they do not look like the numbers have been removed, but rather they were never stamped to begin with.

Well, in the 2nd picture, upper right corner of the rectangle is "round" as if a drill was used.  Anyway was it common in the US at WWII that numbers were not stamped or erased?

I don't think so: All letters and symbols are raised, and there is this white stuff on the edges. It looks like dirt which can not be removed with a rag. The blank rectangle is black (i.e. "clean") and has the same white edges. So, it is raised like the letters.

identification plates are generally made in one large batch for a particular model, with individual serial numbers stamped on with a hammer and die.

this was used on the avenger i and avenger ii aircraft for starting the engine, found in an Australian navy manual from that era.

I have the same model gearbox, which is only stamped on the serial number side "R1404". The gearbox is mounted on a trommel used for mining purposes.

I suspect the reason for this has nothing do with aviation and better fits at our history or statistics stackexchange counterparts.
Information about the production capacity of the enemy is of major strategic importance. Using the serial numbers of a relative few aircraft one can make a quite accurate estimate of the total number of aircraft produced. This was found out during world war II and is known as the German tank problem.
What I suspect is that after this methodology was developed, producers were asked to withheld the serial numbers from their products and/or replace them by a cryptographic equivalent.

Thank you.　　It was beyond my imagination.  It makes much sense.

Possible, but IIRC they just stopped using serial numbers with obvious sequence. (Non-serial serial numbers, LOL.) This prevents statistical analysis from the numbers, but allows parts tracking. http://en.wikipedia.org/wiki/German_tank_problem#Countermeasures Of course there might have been a transition period...

I think this is a little unlikely - as it was a hot topic during the war, asking  hundreds of suppliers to stop numbering parts would almost certainly leak out, and just alert the other side to the vulnerability, negating its value. It only worked because it was a secret.

The item shown is an inertial starter which was used for various purposes including opening the bombay doors of B-17s.
The serial number was stamped into a strip of zinc or lead that was affixed to the plate as shown below:

The strip could have:
(1) deteriorated and fallen off
(2) been removed when someone cleaned the item
(3) melted off in a fire
Since it was in a crashed aircraft, it would not be surprising if the strip was damaged or removed somehow.

There may be a simpler explanation than missing lead strips or a deliberate attempt to avoid the "German Tank Problem" ... someone may have decided, between the design of the casting, and the manufacture of that component, that there wasn't enough value in the serial number to justify the time and expense of stamping it and recording the serial number in a ledger.
If a small company was swamped with orders for thousands of components on impossibly short timescales under wartime conditions, this saving is quite likely.
Image shows a plate from a pre-WW2 machine tool, where there was no need to hide the production quantity - it was simply never recorded on the plate. However on these tools, the the serial number was stamped somewhere else on the machine. Ironically, the Admiralty version of some of these tools supplied during WW1 was faithfully logged by serial number and can be traced to the original ship the lathe was supplied to.


text:
Turbulence from hot weather?
My introduction flight was canceled because of "the turbulence due to heat". They called half an hour before the time of the flight (Cessna 172).
I'm okay to reschedule it but I'm a bit confused:

If it was "due to heat" why did they call right before the flight? We have had this heat the whole week, or even greater (≈ +31°C). Is it possible they didn't know there was turbulence? How do they even know?

How can the heat cause turbulence?

Thanks!

It seems a bit excessive, but it depends on local conditions.

Weather forecasting is not a perfect science, forecasters can predict with reasonable accuracy how the conditions will be over a large area, but there will often be significant variations within that area. There's no way to predict a week ahead of time how conditions will be over an airport with enough accuracy to cancel an introductory flight.
The sun heats the ground, which heats air, causing it to rise and expand. Cooler air falls and contracts, then gets heated and rises again. This cycling is called convection. Air moving up next to air moving down causes the air in the boundary between to rotate. This rotation happens all the time in air, the hotter it is the more energetic the rotation becomes and eventually it causes chop or turbulence which is unpleasant. Every day is different, variations in weather patterns can mean that two days with the same air temperature can have different air conditions, for instance an overcast day has less sunlight hitting the ground, so less convective weather.
Conditions can change throughout the day as well, mornings are usually smoother than afternoons, some days are flyable all day, other times conditions may deteriorate relatively quickly. What most likely happened was that flights came back reporting unpleasant flying conditions and they made the decision to cancel introductory flights as you wouldn't enjoy getting tossed around like a shoe in a dryer, and you may even throw up.
As for why they didn't tell you sooner, they wanted to fly, that's why they are there. This isn't uncommon, when I was in training I would sometimes get called in the morning telling me flying was off. Even today with a full instrument rating I'll still occasionally get to the airfield and then make the decision not to fly because of conditions. It's just part of flying.

The weather creating the conditions is atmospheric convection from a combination of the sun heating the ground (unevenly) and instability of the atmosphere in between the ground and 5-10,000 feet.
The instability occurs when the lapse rate (temperature drop with altitude) is steep, so that if a package of air is warmed at the ground and something gets it moving up, it wants to go higher faster, the higher it goes. More or less like a hot air balloon.
So you end up with a vertical circulation in the atmosphere between the ground and cloud base. Air rising, and beside it, air falling.
The vertically rising columns of air are called Thermals.  If the humidity of the air is high enough, cumulus clouds form at the top of the thermal as the air cools to the dew point at 5, 7, or 10000 feet or wherever.
Gliders exploit this vertical circulation to remain airborne.  For power pilots, it causes an unpleasant ride as you constantly fly through air that is rising, then air that is falling to fill in for the air that was rising.
Anyway, they called you before because the weather conditions were rough, due to that kind of thermal activity, and they knew there was a high risk you'd get airsick, which is bad for intro flights, as you can imagine. They were playing it safe for a potential long term customer.
It'll be worst between 11 am and about 4 pm and if your flight was say, scheduled for 1 pm, and the required conditions are present, the chances are really high it'll be too rough. If the winds are high, it breaks up the thermals and makes the ride even choppier, so worse still.  I would never take anybody new flying on an afternoon with lots of convection and especially convection + high winds.  They'd be barfing within 20 minutes.
Next time you book your flight, try to book it for early morning, say 8 or 9 am, when the air will be silky smooth even if it's going to be a convective day. Or, evening, say after 5 pm.
At some point later you'll find out if you have a problem with air sickness in the bumps.  Generally even if you do get sick, repeated exposure desensitizes you and the airsick problem goes away.  If it is a problem, spending some time on a park swing can help with the desensitization.  It's basically a variation on seasickness.

They cancelled half an hour before, not the day before. I'd say they had just been up for a flight and went "nope this is too much for a rookie"

@ben depending where you live there may be short term weather as John describes. As a VFR student pilot you may find yourself at the airport seeing if conditions improve in the minutes prior to a flight. But for a discovery flight, being (at risk of) overheated and nauseous didn't sound too fun.

Ooops I overlooked the half hour part.  I had it in my mind that they called day before, because in soaring world, they use weather forecast tools that predict things like convective activity. I revised the key bits.

Aside from potential motion sickness, the turbulence will also make control more difficult, particularly for someone on an introductory flight who has never flown an airplane before. They wouldn't also wouldn't want to potentially turn someone off from flying by taking them up with a lot of turbulence on their first flight, possibly giving the impression that flying is always like that in small planes.

As other answers have mentioned, differential heating, from different levels of light absorption of areas of the ground near each other, can cause turbulent air in sunlight, and how turbulent that ends up being can be unpredictable.
I have also flown near farmland which in the summer can massively change light absorptivity overnight - freshly-plowed fields are very dark and can be right next to lighter-colored crop or fallow grass fields.  (FAA Glider Handbook, chapter 10, page 10-4 mentions dark ground and especially "large tilled black soil field" "heat quicker than grass covered fields". )

Thermal convection exists even over perfectly homogeneous surfaces. Heterogeneity does change the profiles somewhat, but not drastically.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

authors: Vladimir F Героям слава


text:
What is the difference between fuel exhaustion and starvation?
Is there any technical difference between fuel exhaustion and starvation? And what does it mean if a pilot says he has a "fuel shortage"?

Fuel exhaustion means there is no more fuel on board the aircraft. Fuel starvation means there is fuel somewhere, but it isn't available to the engine(s) for any one of a number of reasons: pilot error, blocked fuel lines or valves, malfunctioning fuel pumps etc. You can read a study of exhaustion and starvation incidents here.
A "fuel shortage" isn't a formal aviation phrase as far as I know, but "minimum fuel" is a formal phrase with a specific meaning. This is from the FAA's AIM 5-5-15:

Advise ATC of your minimum fuel status when your fuel supply has reached a state where, upon reaching destination, you cannot accept
  any undue delay.
Be aware this is not an emergency situation, but merely an advisory that indicates an emergency situation is possible should any undue
  delay occur.
On initial contact the term “minimum fuel” should be used after stating call sign.
EXAMPLE− Salt Lake Approach, United 621, “minimum
  fuel.”

This question has some more information.

I would opine that fuel exhaustion would be one cause of fuel starvation

I imagine fuel exhaustion means you've run out of fuel. Fuel starvation doesn't necessarily mean you've run out of fuel, just that your engines aren't getting. Perhaps from a clogged filter or line.


text:
What is the the origin of 12,500 pounds in the FAA's definition of large aircraft?
According to the FAA's definitions in 14 CFR 1.1, a Large aircraft is an "aircraft of more than 12,500 pounds, maximum certificated takeoff weight." I have heard this threshold was set based on the DC-3, but that makes no sense to me. Also, there doesn't seem to be any common-sense/international connection to kilograms (i.e. 12,500 pounds is roughly 5670 kg, not a nicely rounded-off 5700 kg).
What is the origin of 12,500 pounds being the cutoff between Large and Small aircraft?

Well, you can't have number that's round in both pounds and kilograms and FAA works in pounds. Regarding Dc-3, it does not make sense to me either, because it's MTOW is a bit over twice as much (25,199 lbs).

Sorry, bringing pounds vs. kg into the question was only to suggest that the requirement doesn't seem to be based on any international standard. I flew a PC-12 for about a year and know their books/specs are metric-based and have been converted to US standards.

There is nothing to be sorry about. It was just a bit unclear why you brought it up, and now you explained it.

Actually, 12,500 pounds converts nicely to 6.25 US tons (2,000 pounds to a ton).

The answer by pithblot is more or less correct. The 12,500 lb. limit was chosen as an approximate halving of the DC-3 gross takeoff weight.
Consider the following quote:

As noted earlier, when first promulgated, the 12,500 lb. weight limit
could be understood in light of the general use of the DC-3, an
aircraft with a maximum gross takeoff weight of 25,000 lbs. and
carrying from 21 to 25 passengers in airline service... The imposition
of a 12,500 lb. gross weight maximum, by effectively limiting the
number of passengers that could be carried as well, did indeed protect
the local service carriers' interests.

(U.S. House of Representatives, 94th Congress, 2nd Session, 1976, pg. 48)
References:
U.S. House of Representatives, 94th Congress, 2nd Session. (1976). The future of aviation: Hearings before the subcommittee of aviation and transportation R. & D. of the committee on science and technology [no. 82]. Washington, D.C.: U.S. Government Printing Office. Retrieved from Google Books.

If you take a look at FAA FAR 14 CFR 23.3 - Airplane categories. you can see the amendment history linked at the bottom. This will take you through a series of changes made to the regulation as well as to the creation of part 23 in 1964 and some provide some background/history for some of the changes. It looks like in 1964 the 12,500 LB limit was not part of Part 23. It was likely included elsewhere so I cant yet trace this full history. However in the amendments that appeared as part of Federal Register: 52 Fed. Reg. 1619 (Jan. 15, 1987). (Page 1806) they go into some specifics and it appears that the weight was chosen as it was somewhere in the middle of the over all range.

Since 1953 the airworthiness standards have distinguished small from
  large airplanes by a 12,500 pound maximum certificated takeoff weight
  -(MCTW) limitation regardless of the type of operation. When this weight limitation was established, little concern was expressed that
  this demarcation would eventually become questionable with regard to
  airworthiness standards for an airplane of the commuter category. At
  that time, there were few airplane designs near this 12,500 pound
  limitation; i.e., they were either considerably above or below that
  weight.

Effectively at the time (1953) all "small" planes were well below that and all "big" planes well above that. Unfortunately this does not shed any light on your DC-3 note.

The DC3 was the backbone of reliable air transportation and way ahead of its time....the wonder metal Aluminium. Deice. Autopilot. Two pilots flight crew. Hostess. Blind flying equipment. Comfortable. Reliable.
It set the standard in many areas...I read somewhere that the rudder force limit OEI of 180 lbs is derived from the DC3. Likewise, the Gulfstream 1 cabin crossection was chosen to be same as the DC3, (I guess because it worked - it was comfortable and looked right) and this carried through to the G2 and many corporate jets.
A light aircraft was considered to be less than half the weight of a DC3 - I was told this many years ago. Can't give a reference, can't confirm if it's true or not. It's just one of those aviation things, maybe even common sense?

Welcome to Aviation Stack Exchange.  Your answer sounds like it could be true, except that you haven't provided any actual references for your assertions.  This site is not a forum, but rather a question and answer site with hard verifiable references being the standard for correct answers and upvotes.  Your knowledge and experience are valued here, but as written, your answer would better fit as a comment to the original post.

Don't get discouraged by comments like the one above. We all have countless nuggets of knowledge that we cannot prove by some Internet link. While it might be considered a rumor, I found your answer helpful. +1.


text:
What is a good flight simulator for a beginner?
I'm in the UK and I wish to learn to fly starting with a home computer simulator.
I have never flown and I am only interested in light aircraft. I need instruction from scratch: what the instruments are for, starting the aircraft, everything from the very start.
I need someone to recommend to me a good home computer simulator which comes with basic flight instruction.

If you seriously want to learn to fly and get a license you need to go to a CFI and take lessons from him or her. A flight sim will not help you at all in this situation.

MS Flight Simulator has a built-in training program that walks you through it. For X-Plane, there are tutorials available.

Hi Howard. Welcome to Aviation.SE. Have a quick read of the help centre, especially about what is on and off topic and what kind of questions are expected.Any question containing "can you recommend" is likely to be off topic. In addition, your question is very broad and cannot be answered with concise, factual answers. Do please ask specific questions (remember, search first, many will already have been asked) and have a look through the existing question list for a feel of how things are done around here.  Good luck. We look forward to more from you.

You might also find this Q&A interesting.

Closely related

Most commercially available flight simulators (MS FSX, X-Plane, Prepar3d) can make excellent training tools for a budding pilot.  But do take this caution to heart.
The cup has to be empty before it can be filled.
Applied to flight training, do not attempt to instruct yourself how to fly.  At best, you will develop a lot of bad habits which a CFI will have to root out and correct prior to being able to teach you correct airmanship techniques.
On the other hand these kinds of games, when set to use realistic flight models, can be excellent tools for practicing skills you learned when you flew with a CFI in the real thing.  Using a realistic simulator game in parallel with real world flight training can save you a lot of time and money in your training.  These sim games are also excellent for instrument training as much of the required instrument skillset is easily modeled by the computer.  While not approved as an official Flight Training Device for logging official flight time, these sims are extremely realistic - so much so that the same mistakes I make in FSX I will make in the real thing!
One cautionary note:  sims like FSX do model a number of details correctly whereas other ones like dangerous weather, flying at the extreme edges of the envelope, etc are not.  There are a number of scenarios (eg flying into thunderstorms) you can do in FSX which will get you killed in the real world.  Approach learning to fly in a game with caution and any instruction you receive from a CFI should supplant game derived knowledge.


text:
How can an aircraft owner/operator track unauthorized flights?
Is there a product or some other way to track an aircraft's use, even if the pilot doesn't file an IFR flight plan, to let the owner know if it's used without authorization?

Spot Trace

Possible duplicate of Is there a site that tracks all flights?

I'm curious about what your situation is where it's easier to monitor a plane with online flight tracking than old fashioned security measures like door locks or a closed hangar.

Yes, its called a Hobbs meter or tach timer.

There are security devices like Securaplane which can keep track of airplanes, and set off alarms under certain conditions.

I'm not sure how this is off topic, we already have a question about keeping planes from being stolen.

@fooot I'd say because this is more of a product recommendation than a generalization about how to keep them from getting stolen.

I hate it when the kids sneak the Cherokee out of the garage at night for a joy ride... ;)

@RonBeyer -  I think this is only a product recommendation question if there's one method/product to track unauthorized use of airplanes, but I suspect that there is more than one mehod and many products, so an answer can be generic enough to not become a product recommendation.

The first thing that comes to my mind would be one of several GPS based fleet vehicle tracking systems. Such a solution would be an appropriate application for a fleet of aircraft, but would probably be cost prohibitive for only one or a few aircraft.

The owner could do regular checks of the aircraft's Hobbs meter, and if the times don't match what the log is saying, then there could be some red flags being thrown.
If someone it out to deceive, I'm sure they could get around this, but maybe then, the problem is giving access of expensive equipment to people who aren't trustworthy.
There are GPS tracking systems that could keep a movement log in memory.


text:
What is the relation between the boundary layer and lift of an aerofoil?
Why do we try to reduce the thickness of the boundary layer over an aerofoil as much as possible if the boundary layer is responsible for creating lift?

You're right--the boundary layer is related to lift production since, in a subsonic example, "guides" the air relative to the airfoil shape and enables the necessary flow accelerations that create the pressure differential and downwash.  However, a thick boundary layer is not necessarily a good deal, especially on an airplane wing.
I think that this answer makes a good reference here.  The thicker than a boundary layer is, the greater the velocity and pressure gradient across it.  Therefore, the chance of flow separation (think of stall, when flow is no longer following the airfoil contour and is creating a ton of drag and not much lift) is also higher.
This consideration is further outlined here, in a master's thesis from TU Delft (a major technical university in the Netherlands).  If the boundary layer is allowed to grow and is allowed to remain laminar, separation occurs relatively early, leading to dramatically increased drag and a similar reduction in lift.  Artificial "tripping" (i.e., the introduction of turbulence) of the boundary layer prior to laminar separation re-energizes the boundary layer and allows it to remain attached for longer.  It can also decrease your drag by some amount, but that's another story unto itself.  This (or some more active sort of boundary layer control) is what I'm guessing you're referring to when you talk about keeping the boundary layer thin.  It is, with the exception of circulation control and insofar as I'm familiar with it, related to energizing the boundary layer to delay flow separation as long as possible.

Artificial "tripping" of the boundary layer from laminar flow to turbulent-attached flow is in fact the principle behind vortex generators which are often used to improve the low-speed/high-angle-of-attack performance of STOL aircraft.

The thicker the boundary layer is the smaller will the velocity gradient become: $Gradient=\frac{\Delta V}{h}$. For constant $\Delta V=Free_Airflow_Speed-Airflow_Speed_on_Surface$ a bigger thickness $h$ makes a smaller gradient.

I wouldn't say that the boundary layer is responsible for creating lift, even if the real world friction enables the creation of circulation and therefore lift. It is mainly responsible for the drag.
Why? Take a look at airfoils in potential flow: they have lift but neither drag nor a boundary layer. Lift is created due to a pressure difference between the upper and lower side of an airfoil and you don't need any boundary layer to explain this pressure difference.
However, you do need a boundary layer to explain drag. The no-slip condition on the airfoil surface creates a layer with a high velocity gradient (from zero on the surface to $V_\infty$- the freestream velocity). Its thickness depends mainly on the viscosity the fluid around the airfoil:

No viscosity at all means no energy loss and therefore no drag.The velocity gradient can be infinite and the layer thickness is zero.
With higher viscosity the particles won't be able to follow such high velocity gradients and the distance between the no-slip surface to the freestream flow around the airfoil will be bigger: the boundary layer will be thicker. The drag will be higher too.

I think the better way of putting it would "viscosity" is essential for lift rather than boundary layer is essential. If it were not for viscosity, the fluid wouldn't want to follow a curvature, leading to acceleration and decelerate and consequently decrease or increase the pressure. The pressure difference creates a net force in different directions. The force normal to free stream direction is lift (or could be negative lift depending on direction). The one parallel to the free stream is thrust or pressure drag (depending on direction). The layer of fluid closest to the surface sticks to the surface and an average momentum exchange with molecules above it leads to deceleration of flow and consequently the growth of the boundary layer. The boundary layer is essentially our concept of how far this effect is significant above the surface. And this is what causes skin friction drag. From point of view of the surface moving through the stationary fluid medium, the fluid molecules are trying to stop it from moving through the fluid and that force is the skin friction drag.
Also regarding the relation between lift and boundary layer, the boundary layer alters the apparent shape of the aerofoil surface, which can change the expected lift production.

Upvoted only for the last sentence.

The boundary layer is related to lift production, but indirectly. The incoming flow not only sees the shape of the airfoil but also the slow-moving air adjacent to the geometry. This effect is captured by the displacement thickness, as illustrated in the image below:

Image source
The formula of the displacement thickness is given by:
$$\delta^*= \int_0^{\delta} {\left(1-{u(x,y)\over u_e(x)}\right) \,\mathrm{d}y}$$
This is the equivalent thickness that when added to the airfoil captures the effect of the boundary layer on the external flow.
As you can see, the airfoil + boundary layer is thicker, and also has lost part of the curvature that is present in the airfoil. The airflow leaving at the right of the image will not be pointed downwards as would be the case without a boundary layer.
The amount of downward turning that is experienced by the airflow is directly proportional to the amount of lift being generated.
In summary, we can say that the boundary layer acts as an intermediate layer, that reduces the curvature of the airfoil, and thereby reduces the amount of lift created. By reducing the thickness of the boundary layer, this effect is minimized, and more lift is created.

It is not the boundary layer per se that creates lift. It is the circulation around the airfoil. For that to get started, a starting vortex that is left behind on the runway, has to be produced. And that is created through boundary layer separation near the trailing edge of the wing.

Without boundary layers we would have a circulation-free flow around the airfoil with very high flowspeed where the flow rounds the trailing edge to a stagnation point near the trailing edge on the upside of the wing. With an absolutely sharp trailing edge, flowspeed would go towards infinity, and we would need exactly zero viscosity to avoid the production of a boundarly layer that would separate to create a starting vortex.


text:
Why is a wing tip's front edge tapered?
I am beginner and I want to understand the advantage of a tapered wing tip front edge beyond reducing the mass. How does this minimize or effect vortex drag, etc. Can someone help me to visualize this scenario please?
I have captured the screenshot from the video on YouTube.

Relevant: http://aviation.stackexchange.com/a/19477/8749

More precisely, are you asking 1/ why the chord is constant, then reduced at the tip, or 2/ why the chord reduction is done with the leading edge rather than the trailing edge or both?

Possible duplicate of How does the raked wingtip of the Boeing 787 work?

Duplicate?  Like how "What's 20 minus 4" is a duplicate of "what's 4.01 squared" just because "16" figures prominently in both answers?  For somebody who has THIS question, he isn't going to look halfway down the answer to something asking about the 787 to find what he's looking for (even though it's there).  This is a reasonable question that stands on its own, with a good, and direct, answer.

The swept-back wingtip has been successfully employed by water fowl for many millennia. The use of composite structures has made the three-dimensional shaping of wingtips much easier, and the first airplanes to use increased sweep at the wingtip were indeed composite gliders such as the Schempp-Hirth Discus.

Seagull (left) Schempp-Hirth Discus 2 (right, source)
In the times of metal wings, Dornier introduced their TNT (Tragflügel Neuer Technologie, in English: Wing of new technology) on aircraft like the Do 228, Do 328 and the Dornier ATT flying boat. It used a triangular wingtip with no change in trailing edge sweep, which is easier to manufacture in aluminium.

An Air Alps Dornier 328-110 landing at Fiumicino Airport, Rome, Italy, viewed from Ostia Antica. Picture by Makaristos.
Boeing has now introduced this detail as the "raked wingtip" in the 787 and the 747-8. Compared to a straight wing, a swept wingtip offers some benefits;

Higher sweep lowers the lift curve slope. This helps to reduce the lift contribution (and, consequently, the bending moment!) of the wingtip at high angles of attack. Therefore, raking the wingtip will result in a lower maximum bending moment.
The sweep also shifts the center of pressure of the wingtip backwards, adding a negative torsion moment. This moment lowers the angle of attack over the whole outer wing in gusts and at high load factors, again helping to lower the maximum bending moment at the root.
It allows to combine a near-elliptical circulation distribution over a wide range of angles of attack with good stall characteristics. The lower lift curve slope of the wingtip lets it stall at a higher angle of attack and reduces its lift contribution relative to its area at increasing angle of attack.

In order to prevent the outer wing from stalling first, you want to give it a lower lift coefficient, which can be achieved by locally adding chord over what is required for an elliptical wing planform and a lower local incidence. However, doing so will still add lift proportional to the local chord when the angle of attack is increased. Now the wing will show the ideal elliptic circulation distribution only for one angle of attack. By adding sweep to the outer wing, its lift curve slope is reduced, so its off-design circulation distribution is closer to the elliptic ideal.


text:
Are animals straying onto the runway considered to be a runway incursion?
Are animals on the runway defined as a runway incursion?

Not if they were cleared to cross by ATC.

No comment for the previous post.

I have to link to this story: http://aviationhumor.net/deer-on-the-runway/

The FAA defines a runway incursion as:

Any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle or person on the protected area of a surface designated for the landing and take off of aircraft.

So no.

This is the ICAO definition as well

They are considered a runway obstruction not incursion.

Can you provide a reference for this? Is it valid worldwide or in your country?

I've always heard 'obstruction' in reference to inanimate objects on the runway -- storm debris, blown tire remnants, etc.  Wildlife hazard is the the term I've heard most commonly used to warn of critters on the runway.  Here in Florida, tortoises and alligators routinely wander onto runways.  The tower usually redirects traffic to avoid them until they wander off.

Perfect answer, master!

@eduardoguilherme The reason this is not a perfect answer is that you don't know if it is true or not.

While in Alaska, other creatures are obstructions...http://www.cbc.ca/news/canada/north/seal-runway-alaska-airport-1.4372369

It's true, at least in the United States. I have worked operations for many years.

@mins, why does the distinction matter?  An animal on the runway has the same effect on an airplane hitting it worldwide, regardless of how we label it...

Well, in my opinion it is a runway obstruction, not a runway incursion.

No but they are a FOD hazard!
Reminds me of a funny ATC conversation I heard out at KRVS a long time ago:
Tower: Cessna Niner Fife Four Fife Niner clear for takeoff Runway one niner right.
Cessna 95459: Unable to comply…there appears to be a skunk on the active.
Tower: …well if I had a .22 I’d grease him for you, but continue holding short and let me know when he’s clear of the active.


text:
How does the MiG-23 fuel system work?
In what order are the fuel tanks on the MiG-23 used? In other words, which tank is used first, then second etc.?

These guys could probably answer this question.
It'll cost you $10, but you can obtain a MiG-23 POH here which should have a systems description in it for the jet's fuel system.
https://www.flight-manuals-online.com/product/mig-23/

There are different models of the MIG-23 with different internal and external fuel tank configurations. The usual procedure is to use external tanks first, then internal fuel. If you have tanks on the wings you use the outboard tanks first, then the inboard ones.

do you have any source?


text:
What equipment does an A320 need in order to operate under RNP 2?
What are the aircraft equipment/systems eligibility requirements for Airbus A320 airplanes to operate in RNP 2 airspace?

In which country? See page 32-33 of this ICAO presentation. For India, this operating circular is relevant, for Autralia this is this one. RNP is not an airspace, but a navigation mode like RNAV. All RNP modes and RNAV are part of PBN.

Are dual navigation autopilot and GNSS systems required for RNP2 despatch purposes?

@user175574  No, a single autopilot would be fine, and in fact I suspect that no autopilot wouldn't disqualify for RNP 2, at least in the US.  Also, GNSS wouldn't be required in MOST airspace, because DME/DME updates are plenty accurate for RNP 2, if/where there are enough Navaids close by.  Over the ocean, then yes you'd need GNSS.  RNP 2 isn't very demanding -- essentially any A320 has more than enough to meet the requirements for it.

At least one engine :)

According to ICAO/EASA till 12/2015 Version.
And from Airbus getting to grips with modern navigation.

Regulatory Authorities have published standards for specific
  airspaces. Provide certification and operational requirements for
  Basic RNAV (RNP-5 Type) and for Precision RNAV (RNP1 Type) within
  European airspace (refer to Annexes 5.1 and 5.2 at the end). FAA Order
  8400.12A addresses RNP-10 operations in oceanic and remote areas (refer to Annex 5.3 at the end). Also RNP AR required equipment is
  specified in several sources and the FCOM manual of airbus. In
  addition for RNP 2 specific terminal and approach operations the
  requirements are specified on the approach charts of airports that implementing it.

Most of the operators/airlines are using the standard required equipment for RNP 1.

According to FCOM A319/A320/A321 FLEET / PRO-SPO-51 P 8/10 The minimum navigation equipment required to enter RNP 1 airspace is:
‐ One FMGC
‐ One MCDU
‐ One GPS
‐ Two IRS
‐ One FD in NAV mode
> ‐ Two NDs (the temporary display of ND information via the PFD/ND
  switch is permitted on one side).

Some helpful information also about RNP 2 you can find also here: http://www2010.icao.int/NACC/documents/meetings/2013/pbn2013/ops7-en.pdf
Moreover Airbus company under PRO-SPO-51 P 5/10 in FCOM refers as RNAV1(2)
so it takes exactly the same equipment for RNP 1.
Let me know if something is different, or if you have different information from another specific-related documentation.


text:
Can an Indian operator get approval for ETOPS-120 without first getting approval for a lower ETOPS rating?
If an A320 aircraft equipped with CFM 56-5B engines is certified capable of 120 minutes ETOPS by the manufacturer as per its AFM, can an Indian operator directly request operational approval for ETOPS-120 from the DGCA? Is this possible without getting approval for a lower rating first, i.e. ETOPS-75 or ETOPS-90?
Note: the request for approval would be based on (a) AFM certification, (b) ETOPS training  to flt. crew and maintenance, (c) implementation of ETOPS maintenance and operational policies and procedures (d) ETOPS CMP compliance, (e) satisfactory in-service reliabilty and operational experience of approx 10 years with a fleet of 15 aircraft on non ETOPS sectors

Whose regulations are you operating under?

Operating under Indian  DGCA regulations

The short answer is yes (unless the DGCA has some unusual process with no public documentation). But be careful: the manufacturer does not certify an aircraft for ETOPS; only a regulatory agency can do that. The manufacturer can put in its books what it thinks is possible/acceptable, but without approval from the local regulatory authority, an operator cannot legally use those books for continued airworthiness. Generally, though, the big manufacturers work with the big local authorities worldwide to make sure that the books will pass muster internationally. But that does not mean that individual operators are exempt from needing to obtain local certification for their specific operations and airplanes. Given the basis you've listed, an operator would have a very strong case, in my opinion.


text:
What is the difference between a forward, aft, high and low center of gravity?
I would like to know the difference between when the center of gravity (CoG) is forward and aft? And high and low?
I already know that the lower the CoG, the greater the static lateral stability. A forward CoG is generally more stable than an aft CoG. So does this mean that a low CoG is the same as an aft CoG?
Note: If the effects of an AFT CG is not the same as Low CG, then what's the effect of each one of them or what's the difference between them?, and most importantly when is the CG is AFT or Forward?, and when is the CG Low or High?

Welcome to the site! I've reworded your question but I may have got it wrong, so please correct it as needed. However, I'm not sure exactly what you're asking: obviously "low" doesn't mean the same thing as "aft", so are you asking if the effect of a low CoG is the same as an aft one? If you can explain a little more about what you mean I think it would be helpful.

Yes im asking if the effect of a low CG is the same as AFT CG and if not then what's the difference between them?

As a pilot, I've only used forward/aft CG. As a motorcycle rider, I've only used high/low CG. Knowing the difference between the two, I'm not really sure that a high/low CG change would even affect an aircraft unless it moved the CG forward or aft. Plus, I don't know what would really constitute a high or low CG in an airplane. I don't know that you could move the CG far enough within the physical limits of the aircraft to make a noticeable difference.

@Shawn Are you talking about moving the CG up/down to make a noticeable difference? Because if you are implying a front/back won't either I'd suggest the next time you go flying to trim the airplane out then have your passenger slide the seat forward or back about 4 inches and watch what the plane does :)

@RonBeyer Talking about up/down in an airplane. Front/Back will most definitely affect the flight characteristics of the aircraft.

There are also a number of answers here in aviation.se about lateral CG limits in helicopters.

I'm not sure I'm understanding what you're trying to get at, but let me try to answer the sentence:

most importantly when is the CG is AFT or Forward?, and when is the CG Low or High?

Whether the CG is aft or forward refers to its position along the longitudinal axis of the airplane, that axis that runs from the aircraft nose to the tail. Usually if people refer to just "the CG" they're typically referring to the longitudinal position of the CG as that is generally the most critical. Boeing refers to the longitudinal axis measurement as the BA, balance arm, although the longitudinal CG is usually spoken of in terms of the percent of the mean aerodynamic chord.
Let's say you have a freighter with a single 10,000 lb pallet in it. If that pallet is in the forward most position capable of handling it, the longitudinal CG would be considerably more forward than if the pallet were in the aft most position. Very possibly in either instance the respective forward and aft CG limits would be exceeded. If a loadmaster said only, "I've got a forward CG," he might mean that the load is forward of the forward limit, or he might simply mean that the load is within the limit but more forward than he likes.
Now let's say that we split the 10,000 lb pallet into two 5,000 lb pallets, and we put one of them in that most forward position on the main deck and the other in the same longitudinal position on the lower deck. That wouldn't change the longitudinal CG because both pallets are at the same longitudinal position. However, it would change the vertical CG as measured along the vertical axis. Loadmasters on 747s don't have to worry about the vertical CG because there are no defined limits for it in 747 weight and balance manuals. Loadmasters on 767s, however, do as there are defined limits. If a 767 loadmaster says he has a high CG, he can mean that the maindeck load is too great given how much is in the lower deck. He also might mean that the vertical CG of the maindeck load itself is greater than 42" above the maindeck floor. Boeing refers to the vertical axis measurement as the WL, water line.
Though you didn't ask about it, there is a third axis, the lateral axis, extending from wing tip to wing tip so to speak. Boeing refers to the position along this axis as the BBL, body buttock line, and there are typically limits as to how far from the aircraft centerline the lateral CG can be.

In reference to the BBL, don't put all the pallets on one side of the plane!

@FreeMan Correct, however, it's surprising (at least to me), how tolerant of lateral imbalance some aircraft are, especially the 747. For an example, go to 747.terryliittschwager.com, scroll down to the bottom of the page, and select test load #6 to see what it takes to exceed the limit.

@Terry Thanks for your answer commander, i asked that question from the start to understand 2 of the factors that affect the static lateral stability of an a/c. which are: 1.High wing and Low CG, 2.High Keel and Low CG which i don't understand them much and would really appreciate it if you could lend me a hand and explain to me how do they work or affect the stability. Thanks : )

Reading about CG on a 747 I can't help but think of this tragic video from Afghanistan

@KarimElshawarby As I understand it, both configuration 1 and 2 that you refer to promote lateral stability (i.e. dampen rotation about the longitudinal axis) because they maximize the vertical distance between the CG and the vertical center of the sideways forces on the aircraft. Those sideways forces (the keel effect) thus have a longer moment arm to right the aircraft. See https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/media/pilot_handbook.pdf and search on "keel effect'' and you'll find some good info.

@TomMcW Sobering indeed. I'll never forget receiving the email from National Air Cargo shortly thereafter asking me to remove the entry for N949CA from the menuing of the weight and balance software they used for palletized cargo as they had lost an aircraft.

@Terry Thank you sir so much for your effort : )

Basically your question is a combination of two aspects that were already discussed in quite a lot of detail:
Stability is already explained pretty well in What does it mean for a plane to be aerodynamically stable?. The summary is that forward centre of gravity makes the aircraft more stable, but slightly less efficient, while aft centre of gravity makes it less stable.
The vertical position is then discussed in How do the Airbus Beluga's wing/control surfaces deal with its high center of gravity? In short, vertical position of centre of gravity is mostly irrelevant. The lift in straight and level flight acts on a line passing through centre of gravity and banks with the plane, so it can't create any moment. Only the lateral force in a side-slip can, leading to slightly lower yaw-roll coupling with high CoG, but one does not normally rely on yaw-roll coupling, so it is not very interesting.

The vertical position of the CG on an airplane and its effect on stability is going to depend largely on the position of the wings.  A high mounted wing with a low CG on the fuselage will create a very stable aircraft about its longitudinal axis; a high CG on a low mounted wing will create dynamic instability about this axis.  Many aircraft which are designed for maneuverability e.g. aerobatic aircraft, military fighters, etc. have a shoulder mounted wing where the center of lift lies very close to the center of gravity along the vertical axis creating neutral roll stability.
CGs in the forward range of their approved envelop develop good lateral stability but at the expense of more induced drag as the tailplane or canards are required to produce more lift to counteract the torque the CG creates about the center of lift.  Aft CGs reduce induced drag but lead to lateral instability and can be quite dangerous in a stall or spin due to the diminished effectiveness of the tailplane.

Vertical position of the CoG is IRRELEVANT!

I also suspect you mixed up lateral and longitudinal stability. Longitudinal stability is stability in pitch, that is around lateral axis. As for lateral stability, it is not clear whether it should mean stability in roll or in yaw and that term does not seem to be widely used.

@JanHudec I also thought that the vertical position of the CG was irrelevant. However, I recently had to change some weight and balance software to handle 767 freighters. Much to my surprise (and dismay as I had given them a low quote on what I would charge), I found that there were vertical CG requirements. Thanks to that, I'm working for less than minimum wage. LOL


text:
Why do transport-category aircraft have hard tailwind limitations?
With most transport-category aircraft, even with a 5 km runway, gross weight close to ZFW, using maximum flaps for takeoff, performing an unpressurized, full-power takeoff, the maximum legal tailwind is limited to 10 knots (or 15 knots, depending on the manufacturer) -- why is this?  Clearly in a case like this, the aircraft could take off just fine with a tailwind above the 10 or 15 knot limit, when it takes off with a tailwind at the limit under much less ideal circumstances.
It seems unreasonable that there should be a fixed aircraft limitation for the tailwind component, rather than a limit that varies with runway length, aircraft configuration, temperature, etc..  Yet hard tailwind limitations exist.  Why?

What limitation are you referring to? Please be specific.

Well, you might as well go ahead and specify aircraft or general range of aircraft you are talking about.  There are many aircraft in which opting to not use any packs or pressurization would not gain you anything, because they do not exist.  I never had much luck with downwind takeoffs in a foot-launched hang glider.  Paragliders would probably have an even harder time.  Even when flying for commercial reasons (just noticed the tag).

What happens if you try to throw a dart tail first?

Transport airplanes normally have a certified tailwind limitation, usually 10 or 15kt, and it's simply to provide flexibility in situations where the runway distance is sufficient for a safe departure with a modest tailwind component, so you won't have to abandon a takeoff and go to the other end just because the wind shifts from headwind or crosswind to slight tailwind.  There is also a runway slope factor in the performance data.

It's not just the takeoff length you need to consider. Such a tailwind will impact the climb performance so you might not clear the terrain.

"using maximum flaps for takeoff" - Actually, the optimum flap setting for takeoff is generally well below maximum, since the later stages of flap extension add a little lift but a lot of drag, meaning that the aircraft actually needs more runway to take off at maximum flap than at midflap; at maximum flap, it lifts off at a slightly-lower speed, but takes considerably longer to accelerate to that speed.  All transport-category aircraft can successfully take off with full flaps (this is a byproduct of the certification requirement that they be capable of successfully aborting (1/2)

(2/2) an overweight landing in full landing configuration, with maximum flaps and gear down), but it considerably increases the time and runway-distance requirements for the takeoff.

For jets, the low tailwind limit is primarily because anything more than a slight tailwind can cause engine surging at low power settings, such as the ground-idle setting you're going to be using to turn onto and line up on the takeoff runway.  Prolonged surging can severely damage a jet engine.  Engine damage is not especially conducive to a successful takeoff.

Tire speed is also a consideration.

Airline operations only happen where there is valid performance data. If Airbus or Boeing or whatever other manufacturer only provides takeoff performance data up to a 10 knot tailwind, then at 11 knots, you're a test pilot. Granted, we can probably extrapolate from the 8 knot to 9 knot to 10 knot data and have a pretty good guess what things will look like at 11 knots, but we aren't allowed to operate that way. Same reason that operations stop when the temperature gets too high... you go beyond the charted data, even by 1 knot or degree, you're done.